Purpose: To analyze the effect of implant placement and loading protocols (protocol types) on the survival of single implant tooth replacements in different locations.
Materials and methods: An electronic search was conducted to identify clinical trials regarding outcomes of single implants subjected to different treatment protocols. A weighted mean survival rate for each protocol type in the anterior maxilla, anterior mandible, posterior maxilla, and posterior mandible was calculated. Study design, sample size, and outcome homogeneity were used to evaluate the validation of each protocol type in different locations.
Results: A total of 45 publications (13 RCTs, 21 prospective studies, and 11 retrospective studies) were included. The anterior maxilla was the most reported site (35 studies, 1,391 implants, weighted survival rate: 97.5% to 99.6%). Immediate placement + conventional loading (Type 1C) and late placement + immediate restoration/loading (Type 4A) were scientifically and clinically validated (SCV). For the posterior maxilla (19 studies, 567 implants, weighted survival rate: 85.7% to 100%), Type 1C was SCV. The anterior mandible was the least-reported site (three studies, 42 implants, weighted survival rate: 98.5% to 100%). For the posterior mandible (13 studies, 447 implants, weighted survival rate: 95.0% to 100%), late placement + conventional loading (Type 4C) was SCV. It was not possible to perform a metaanalysis due to the limited number of controlled studies that had the same comparison and considerable heterogeneity in study design.
Conclusion: Differences were found in the level of scientific evidence between the anterior and posterior and the maxilla and mandible, indicating that location is a consideration when selecting treatment protocol for a single implant.
